A Mastodon scheduler for any instance

Content warnings and who sees the post

Most scheduling tools treat every network as the same box of text with pictures attached. Mastodon is not that, and the two fields it adds are the ones that decide how a post is received.

A content warning replaces the post in the timeline with a short line of context until someone chooses to open it. Write it in the composer and it publishes as a real warning, collapsing the text and putting any attached image behind a sensitive-content screen. Communities on Mastodon expect these far more readily than other platforms expect a spoiler tag, and posting without one where one belongs is the quickest way to be muted by people who otherwise wanted to read you.

Audience is chosen per post rather than per account. Public puts the post on the public timelines where anyone can find it. Unlisted keeps it off those timelines while leaving it readable to anyone holding the link, which is what many instances prefer for routine chatter. Followers only goes to people who already follow you. Mentioned people only reaches the accounts named in the post. Most schedulers publish public and nothing else, which quietly rules them out for anyone whose account was never meant to broadcast.

None of these can be changed after a post goes out, so both are decisions made while composing. Scheduling does not change that, it just means you make the decision earlier.

Chains, and what carries through them

Mastodon has no algorithm. Nothing surfaces a good post twice, and nothing stitches related posts together for a reader. So anything longer than one post has to be built as a chain, each part replying to the one above, or it lands as unconnected fragments in a timeline that will never reassemble them.

Write the parts in one composer and sona.to publishes them as a real chain, each part replying to the previous one as if you had sat there posting by hand. Every part carries its own images and its own alt text. Each point can sit under the picture that belongs to it instead of pushing every visual to the end.

The content warning and the visibility you set apply to every part, not only the first. Mastodon treats both as properties of an individual post. A chain where only the opening toot carries the warning leaves everything below it uncovered for anyone who scrolls into the middle.

What a Mastodon post can hold

The 500 character limit most people quote belongs to your instance, not to Mastodon. Administrators can raise it and plenty run higher. sona.to reads the ceiling from the server your account sits on, so the composer counts down against your real limit instead of a number borrowed from mastodon.social.

Images and video both attach to a post, and video takes a moment longer to publish because Mastodon processes it after upload rather than during. A poll cannot sit alongside media, so any given post is one or the other.

Alt text sits closer to a community requirement here than to an accessibility extra, so each image you attach takes its own description. Writing one is optional and the choice stays with you, but an image carrying information the post text does not is the case where it matters, and it is the omission Mastodon readers notice fastest.

Mastodon can already schedule posts

Mastodon has scheduling built in. The API accepts a scheduled time on any post as long as it sits at least five minutes ahead, and the official apps expose it. If you run one account on one instance and post a few times a week, that is genuinely enough and a scheduling tool adds nothing you need.

The built-in version stops being enough once you run more than one thing. Scheduled posts live on the instance holding them, so two accounts on two servers means two queues checked separately, with no single view of what goes out on Thursday. Nothing connects a Mastodon queue to the posts you have lined up elsewhere, and nothing lets you write six posts in one sitting and space them across a fortnight without setting each time by hand.

That is the gap sona.to fills. One calendar covers your Mastodon account alongside every other network you post to, so a week of content is planned in one pass instead of reconstructed across four apps.

Timing when the timeline is chronological

Most networks decide who sees a post after you publish it. Mastodon does not. A post appears in the timelines of the people following you, in sequence, and then moves down as other posts arrive. No wave of engagement lifts it back up, because nothing is counting engagement.

A post reaches whoever was online. That is the entire mechanism. Publishing into your audience's quiet hours gives you a different audience, usually a much smaller one. This is why an account posting three times at 2am can look dead beside one posting once a day at a sensible hour.

Scheduling exists to close the gap between when you have something to say and when your followers are reading. Write when the thought is there, queue it for the window that works, and let it publish on its own. Our guide to the best time to post on social media covers where those windows tend to fall.

Cadence carries more here than anywhere else

On an algorithmic network a gap is survivable, because a strong post can still be surfaced to people who were not around when it landed. Mastodon has no such mechanism. A week with no posts is a week in which your followers saw nothing from you, and no later post makes up for it.

That puts the whole burden on turning up steadily, which is the habit that breaks first when work gets busy. Queueing a fortnight of posts at once is the straightforward fix: the timeline stays alive on the days you do not open the app, and nothing depends on you remembering.